In recent years, materials for forming color images have predominantly been employed as image recording materials. More specifically, recording materials used in systems such as ink jet systems and electrophotography systems; thermal transfer type image recording materials; transfer-type silver halide sensitive materials; printing inks; recording pens; etc. are widely used. In addition, color filters have been used in the displays for LCD (liquid crystal display) and PDP (plasma display panel) and in filming equipment for electronic components such as CCD (charge-coupled device). In these color image recording materials and color filters, in order to reproduce or record a full color image, the coloring matters (dye or pigment) of three primary colors of the so-called additive color mixture system or subtractive color mixture system have been used; however, the current situation is that coloring matters having a preferable absorbing characteristic of light wavelength that can realize a gamut of reproducible colors, and can endure various service conditions do not exist, and thus improvements thereto have been strongly desired.
The ink jet recording method has rapidly spread and continues to be further developed due to the material cost being inexpensive, high-speed recording being possible, the noise during recording being low, ease of color recording, and the like. The ink jet recording method includes a continuous system in which drops are continuously made to jet, and an on-demand system in which drops are made to jet according to an image information signal. In addition, the spray methods thereof include a method of causing drops to discharge by increasing pressure using a piezo element; a method of causing drops to discharge by generating bubbles in the ink by heat; a method using ultrasonic waves; a method of causing drops to be attractively discharged using electrostatic force; and the like. As examples of inks suited to such ink-jet recording, water-based ink, oil-based ink, solid (molten type) ink, and the like can be exemplified.
The performances demanded in the coloring matters used in inks for ink-jet recording include: the solubility in solvents and dispersability being favorable; high-density recording being possible; hue being favorable; having strong resistance to light, heat, active gasses in the environment (e.g., oxidizing gases such as NOx and ozone, and SOx), and the like; excelling in durability to water and chemicals; good fusability to recorded material; low bleeding tendency; excelling storability of ink containing the coloring matter; no toxicity; and further, ability to procure inexpensively; and the like. In particular, as a cyan coloring matter, it is strongly desired to have favorable cyan hue and high print density, and for bronzing phenomenon not to occur, and to excel in various resistances such as light resistance (durability to light), ozone resistance (durability to ozone gas), water resistance (durability to water), and moisture resistance (durability under high moisture environment), for example.
The bronzing phenomenon refers to a speckle phenomenon caused by the association of coloring matters, the ineffective absorption of inks, and the like, in which the coloring matter becomes a metallic flake shape on the surface of the record-receiving material. When this phenomenon occurs, the record-receiving material becomes worse in all of the aspects of luster, print quality and print density. Particularly in a case of using a metallic phthalocyanine coloring matter as the coloring matter, the “bronzing phenomenon” often appears in areas in which printing was performed at high density, and the color balance of the overall image becomes non-uniform, thereby lowering the quality thereof. Furthermore, in recent years, glossy paper is often used as a recording medium having texture near that of photographic; however, when the bronzing phenomenon occurs, variation arises in the glossy sense for the recorded matter surface, and the texture of the image drastically suffers. A coloring matter for which the bronzing phenomenon does not occur is strongly desired from such a perspective.
Phthalocyanine and triphenylmethane based coloring matters are exemplary of the aqueous cyan coloring matters used in cyan inks for ink jet recording. Among these, the phthalocyanine derivatives classified into the following A to H are known as typical phthalocyanine coloring matters.
A: Well-known phthalocyanine coloring matter having a C.I. (color index) number such as Direct Blue 86, Direct Blue 87, Direct Blue 199, Acid Blue 249, and Reactive Blue 71.
B: Phthalocyanine coloring matter disclosed in Patent Documents 1 to 3, etc.
(For example, Cu-Pc-(SO3Na)m(SO2NH2)n; mixture of m+n=1 to 4.)
C: Phthalocyanine coloring matter disclosed in Patent Document 4, etc.
(For example, Cu-Pc-(CO2H)m(CONR1R2)n; m+n=number of 0 to 4.)
D: Phthalocyanine coloring matter disclosed in Patent Document 5, etc.
(For example, Cu-Pc-(SO3H)m(SO2NR1R2)n; m+n=number of 0 to 4, and m is not 0.)
E: Phthalocyanine coloring matter disclosed in Patent Document 6, etc.
(For example, Cu-Pc-(SO3H)l(SO2NH2)m(SO2NR1R2)n; l+m+n=number of 0 to 4.)
F: Phthalocyanine coloring matter disclosed in Patent Document 7, etc.
(For example, Cu-Pc-(SO2NR1R2)n; n=number of 1 to 5.)
G: Phthalocyanine coloring matter disclosed in Patent Documents 8, 9, 12, etc.
(Position of substitution of substituent-controlled phthalocyanine compound, phthalocyanine coloring matter in which substituent is introduced at β-position.)
H: Benzopyridoporphyrazine coloring matter having pyridine ring and benzene ring disclosed in Patent Documents 10, 13, 14 to 16, etc.
Presently, phthalocyanine coloring matters typified by C.I. Direct Blue 86 or C.I. Direct Blue 199, which are widely used for ink jet recording, are characterized in generally excelling in light resistance compared to magenta coloring matters and yellow coloring matters. However, phthalocyanine coloring matters are greenish hues under acidic conditions, and are not very preferable hues as cyan inks. As a result, in a case of using these coloring matters as cyan inks, it is preferable to be used under neutral to basic conditions. However, even if the ink is neutral or basic, in a case of the record-receiving material being acidic paper, for example, there is a possibility that the hue of the recorded matter will change greatly.
In addition, in a case of using phthalocyanine coloring matters as cyan inks, depending on the oxidizing gases such as nitric oxide gas and ozone, which are often exemplified as recent environmental problems, the hue of the recorded matter will change to a greenish color, and decoloring, fading or the like will also occur; therefore, a phenomenon will occur in which the print density of the recorded matter declines.
On the other hand, although the hues are known to be favorable for triphenylmethane dyes, it is much worse than phthalocyanine coloring matters in terms of the light resistance, ozone resistance, and moisture resistance.
In the future, if the field of application of ink jet recording expands and becomes widely employed in display items such as advertisements, the chance for the coloring matters and inks used therein to be exposed to light and oxidizing gasses in the environment will also increase. As a result, it has been increasingly strongly desired for a cyan coloring matter for ink jet recording to have favorable hue, to be low cost, as well as excelling in the above such various resistances. However, it has been regarded as difficult to develop a cyan coloring matter and cyan ink satisfying these requirements at a high level. Although the phthalocyanine coloring matters imparted with ozone resistance up to now have been disclosed in Patent Documents 3, 8 to 12, 14 to 17, etc., a cyan coloring matter has yet to be obtained that satisfies all qualities such as hue, print density, light resistance, ozone resistance, moisture resistance, and not producing bronzing phenomenon, and furthermore, enabling manufacture at low cost. Therefore, it still falls short of adequately satisfying the market requirements.    Patent Document 1: Japanese Unexamined Patent Application Publication No. S62-190273    Patent Document 2: Japanese Unexamined Patent Application Publication No. H7-138511    Patent Document 3: Japanese Unexamined Patent Application Publication No. 2002-105349    Patent Document 4: Japanese Unexamined Patent Application Publication No. H5-171085    Patent Document 5: Japanese Unexamined Patent Application Publication No. H10-140063    Patent Document 6: Japanese Unexamined Patent Application (Translation of PCT Publication), Publication No. H11-515048    Patent Document 7: Japanese Unexamined Patent Application Publication No. S59-22967    Patent Document 8: Japanese Unexamined Patent Application Publication No. 2000-303009    Patent Document 9: Japanese Unexamined Patent Application Publication No. 2002-249677    Patent Document 10: Japanese Unexamined Patent Application Publication No. 2003-34758    Patent Document 11: Japanese Unexamined Patent Application Publication No. 2002-80762    Patent Document 12: PCT International Publication No. WO2004/087815    Patent Document 13: PCT International Publication No. WO2002/034844    Patent Document 14: Japanese Unexamined Patent Application Publication No. 2004-75986    Patent Document 15: PCT International Publication No. WO2007/091631    Patent Document 16: PCT International Publication No. WO2007/116933    Patent Document 17: PCT International Publication No. WO2008/111635